The present invention relates to ball bushings for rotatable or oscillating shafts and in particular to a ball bushing provided with an elastic packing seal for closing the annular space between the shaft and the bushing.
Ball bushings are generally sealed with respect to the journalled shaft by suitable packing materials so that the penetration of alien bodies such as dirt, dust is prevented and the emergence of lubricant from between the bushing and the shaft is also prevented. It is desirable to integrate such packings with the bushing so as to provide a unitary assembly for both storage and installation. In the known designs there is however a drawback which lies in the fact that when the packing or bushing itself is damaged or destroyed, the packing can only be removed and replaced with the greatest of difficulty.
In German patent publication No. 7,238,681 an attempt to overcome the foregoing drawback was made. A housing was provided for the bushing having at its end an annular bulge over which the packing, provided with a cooperating axial lug, was snapped. However, the dimensions of such a design were very large and the attachment of the packing was neither stable or reliable. At very low axial loads, placed upon the packing, the packing was easily dislodged from its seat on the bushing.
It is an object of the present invention to provide a ball bushing with an integrated packing which overcomes the drawbacks of the prior art.
It is another object of the present invention to provide a ball bushing having an integrated packing which is reliable and stable under all conditions of use.
It is still another object of the present invention to provide a ball bushing having an integrated packing which is easily removable and exchangeable.
The foregoing objects, other objects, together with numerous advantages of the present invention will be seen from the following disclosure thereof.